Climate Blog

April 26, 2010,
17:00 PDT

Energizer bunny in a scuba suit

This week I heard a short talk from one of my colleagues, Dr. Yi Chao, about an autonomous underwater vehicle (AUV), that he and his colleagues from NASA’s Jet Propulsion Laboratory and the Scripps Institution of Oceanography have dreamed up called “SOLO-TREC” (short for the very long name "Sounding Oceanographic Lagrangrian Observer Thermal RECharging" vehicle). Now there’s nothing unusual about underwater vehicles – anyone who has seen James Cameron’s 1997 blockbuster movie “Titanic” will be familiar with the idea of using robots to probe beneath the ocean waves. And there’s nothing new about autonomous vehicles – robots that can think for themselves. We have autonomous rovers exploring Mars and you can even buy cars these days that can reverse into parking spaces without your hands touching the steering wheel.

A SOLO-TREC underwater vehicle next to Kyle Grindley, an engineer at the Scripps Institution of Oceanography who helped design it. Credit: Scripps Institution of Oceanography, University of California, San Diego.

The cool new thing about SOLO-TREC is the technology it uses to power itself. It bobs up and down from the warm surface of the ocean, to the colder depths at 500 meters (1,600 feet) down. The robot has several long narrow cylinders filled with oil that, when cooled, changes to a solid wax and contracts by about 15 percent. This ‘phase change’ from liquid to solid and back again is used to power a hydraulic motor for electricity generation and to charge SOLO-TREC’s batteries. The robot’s instruments measure sea water temperature, pressure and salt content profiles and, when it reaches the surface, it phones home the results using a satellite phone. Being self-powered, it can go on like this, bobbing up and down, drifting along and making measurements, for a long time. Previous robots, running on batteries, could only manage a couple of hundred dives before they had to be hauled out and refurbished.
What’s this got to do with Earth’s climate? Well, as the Earth warms, a lot of that heat is stored in the ocean, and the oceans contain enormous amounts of carbon in the form of dissolved carbon dioxide (CO2) and as calcium carbonates from the shells of dead marine creatures. Plus a new study by the National Academy says that ocean chemistry is changing much faster than previously thought because of all the extra CO2 that is being absorbed from the atmosphere. So it’s important to monitor what’s going on in the ocean using the best tools that we have available. From space we can measure a lot of what’s happening at the ocean surface, but we can’t see below. A fleet of SOLO-TREC robots, properly instrumented, could monitor climate change or the effects of climate change beneath the ocean surface, and keep on doing so for years to come.
If you want to see where SOLO-TREC is today, go to this page for the latest results.

April 22, 2010,
17:00 PDT

It's your planet, and our mission

It's clichéd but true: At NASA, every day is Earth Day. We don't just explore the far reaches of the universe; we spend a lot of time looking down at our home planet from space. Amazing things can be discovered from the perspective of orbit, and that's why NASA has over a dozen satellites whizzing over our heads right now. We study the oceans, land, atmosphere, ice and snow, climate change, air quality, solar effects, earthquakes, volcanoes, weather and even the Earth's gravitational field, and there are many more exciting missions planned for the future.

Today on the fortieth anniversary of Earth Day, take a moment to appreciate the majesty and beauty of our home planet with this video we put together.

April 20, 2010,
17:00 PDT

You say to-mato, I say LED lamp?

Photo courtesy of On/Off by D-vision.

Mimicry is the sincerest form of flattery. At least that’s how it goes in the technology world. Today’s researchers are developing solar-powered cells that look and behave exactly like plant leaves — they're green, they blow in the wind, and they absorb light and convert it into electrons. Straight from Mother Nature’s textbook.

Now an illuminating new design has come to the table. It’s less a case of mimicking a plant and more a case of harnessing real-life fruit — in this case, tomatoes. Yep, those acidic little yummies are being used to run an LED table lamp called “Still Light.” The lamp, which comes out of d-VISION, an Israeli internship program for Product Development and Industrial Design, hooks up tomatoes to copper and zinc electrodes. The tomatoes act as electrolytes for the current to pass through and help power the LED. Like all good things, it comes to an end — when the tomatoes eventually rot. This isn’t nature’s solution to our energy problems. But it is a cool new design and might help spur on the next generation of tomato technology.

April 16, 2010,
17:00 PDT

Extreme field campaign

From Patrick Lynch,
NASA's Earth Science News Team

A team from NASA Langley Research Center needed a high and dry place to run their Far Infrared Spectroscopy of the Troposphere (FIRST) instrument last summer and fall. They found it in Chile's Atacama Desert. Photo courtesy of Rich Cageao, NASA Langley Research Center.

How does a group of NASA scientists end up on a barren mountaintop, a hemisphere away from home, 17,500 feet above sea level, and in need of supplemental oxygen to stay focused in the thin air? Like most things in science, this trek began with a question or two.

“The first question is: what is the science that’s important to do? The second is: how do you do it?”

Rich Cageao said it was these questions that led a group of scientists and engineers from NASA’s Langley Research Center to embark on a four-month field campaign to the Atacama Desert of Chile in 2009, from late July to early November.

To study how water vapor absorbs infrared radiation in the high atmosphere and influences the climate, the group needed a site well above sea level. Otherwise, the higher levels of water vapor near the surface would block any attempt at detailed infrared measurements, like putting a thick layer of gauze in front of a camera lens.

A modified shipping container — like the ones shipped on rail cars and tractor trailers — became a remote office for the scientists and home for their instrument called FIRST — Far Infrared Spectroscopy of the Troposphere). Trucks took it from Virginia to California; a ship took it from California to Chile; a truck again took it from sea level to an elevation equal to the base camp on Mt. Everest. And the container – outfitted with windows, a door, an opening for measurements, and oxygen — made it to and from the site in pretty good shape, despite a few snowstorms and gale-force winds.

Here the site is seen prior to grading and preparation. Photo courtesy of Rich Cageao, NASA Langley Research Center.

Once the container was in place at a graded site on a Chilean mountain called Cerro Toco, the team set to working out the kinks with the instrument and power supply. They also worked on adapting to the daily climb from base camp at 8,000 feet to the work site at 17,500 feet.

The conditions kept everyone on their toes, and nothing ever seemed routine, Cageao said. “Warm days, out of the wind, were zero degrees Centigrade. Winds were typically 25 mph, and up to 60 mph," Cageao described the days as extremely taxing. Nothing could be called drudgery. The possibility that something could go wrong required a state of hyper-awareness. “You’re not waiting for something to happen. You never sit around.”

After site work, the instrument, housed in a converted shipping container, was put in place in Chile following a
months-long trek by truck and ship. Photo courtesy of Rich Cageao, NASA Langley Research Center.

But even with the cold, the wind, and the barren, almost lifeless site, Cageao couldn’t pass on the opportunity.

“We have, by nature, that feeling of, ‘we’ve got to get out there,’” he said of many scientists in the office. “We’re much happier in the field. It’s an adventure. It’s good science and it’s challenging.”

So why go to all this effort?

The Earth’s surface emits infrared radiation it has absorbed from the sun. Greenhouse gases partly trap that energy as heat, keeping the planet habitable. But with humans burning fossil fuels and altering the balance of greenhouse gases — and therefore the amount of heat trapped in the atmosphere — scientists need to understand exactly how this process works in order to improve predictions of climate change.

“The primary greenhouse gas on Earth is not CO2. It’s not methane. It’s water vapor,” Cageao said. “And when you drive up the temperature of the atmosphere, you drive up the water vapor, so you better have this right. Having it pretty close isn’t enough.”

Cross posted from NASA’s What on Earth blog. Patrick is based at NASA’s Langley Research Center in Hampton, Virginia.

April 8, 2010,
17:00 PDT

Small but beautiful Guinea-Bissau

This image, which was taken by the Landsat satellite on 1 December, 2000, shows Guinea-Bissau, a small country in West Africa. Complicated patterns can be seen in the shallow waters along its coastline, where silt carried by the Geba and other rivers washes out into the Atlantic Ocean.

April 7, 2010,
17:00 PDT

Green show, that is

NASA's Atmospheric Infrared Sounder (AIRS) instrument has been chosen as a Best of Green Award winner in treehugger.com's Science & Technology category. TreeHugger called it "the best new tool for climate science" and said that without AIRS, "our understanding of the planet's climate would be much poorer."

AIRS is one of six instruments onboard NASA's Aqua satellite. Launched into Earth-orbit on May 4, 2002, AIRS, along with its partner microwave instrument, the Advanced Microwave Sounding Unit (AMSU-A), tracks the planet's water and energy cycles, climate variations and trends, and the response of our climate system to increased greenhouse gases. Termed the "quintessential greenhouse gas sensor of our time," AIRS has produced the first global satellite map of carbon dioxide [CO2] in Earth's mid-troposphere, an area about 8 kilometers, or 5 miles, above Earth. The data it has provided has given us insights into how CO2, which directly contributes to climate change, is distributed in Earth's atmosphere and moves around our world.